Acid-modified biochar increases grain yield and reduces reactive gaseous N losses and N-related global warming potential in alternate wetting and drying paddy production system. (1st December 2022)

• Record Type: Journal Article
• Authors: Chen, Taotao; Liu, Chang; Zhang, Feng; Han, Hongwei; Wang, Zhe; Yi, Benji; Tang, Liang; Meng, Jun; Chi, Daocai; Wilson, Lloyd Ted; Chen, Wenfu
• Is Part Of: Journal of cleaner production. Volume 377(2022)
• Publication Date: 2022-12-01
• Subjects: H2SO4-modified biochar -- Paddy fields -- NH3 volatilization -- Nitrous oxide emissions -- Reactive gaseous N loss; Factory and trade waste -- Management -- Periodicals; Manufactures -- Environmental aspects -- Periodicals; Déchets industriels -- Gestion -- Périodiques; Usines -- Aspect de l'environnement -- Périodiques; 628.5
• DOI: 10.1016/j.jclepro.2022.134451
• Languages: English
• ISSNs: 0959-6526

Abstract

Abstract: Biochar amended soils reduce fertilizer N losses and suppress greenhouse gas emissions. However, biochar can increase NH3 volatilization. H2 SO4 - modified biochar has been studied as a means to achieve the advantages of biochar while reducing volatilization, especially under alternate wetting and drying irrigation ( I AWD ). In contrast to continuously flooded irrigation ( I CF ), I AWD is a water-saving technology that repeatedly dries and re-floods fields. A 3-year field experiment was conducted with two irrigation regimes ( I CF and I AWD ) as main plots and 0 (control), 20 t ha −1 biochar, and 20 t ha −1 H2 SO4 -modified biochar as subplots. I AWD produced 7.6–14.8% more reactive gaseous N losses (NH3 and N2 O) and emitted 2.02 times N-related global warming potential (GWPN ) of I CF . Biochar increased NH3 volatilization by 35.6% in the first year and decreased it by 22.4% and 24.8% in the second and third years, respectively, while H2 SO4 -modified biochar decreased NH3 volatilization each year. The increased NH3 volatilization was caused by the higher NH4 + concentration and pH in the floodwater and surface soil due to increasing N inputs and alkalinity from biochar. The decrease in the following two years was attributed to pH returning to the pre-treatment level and continued biochar absorption of NH4 + from the floodwater. Both biochar and H2 SO4 -modified biochar significantly reduced seasonal N2 O emissions. H2 SO4 -modified biochar coupled with I AWD mitigated the initial increases in NH3 volatilization and reactive gaseous N losses in the first year, and increased grain yield, decreased reactive gaseous N losses, and GWPN compared with the IAWD without biochar throughout the three years. The use of acid-modified biochar could produce higher grain yield with lower reactive gaseous N losses and GWPN for application in the I AWD paddy systems, which benefits sustainable agricultural production. Highlights: AWD produces more reactive gas N losses and N-related global warming potential (GWPN ). Biochar ( B 20 ) suppresses NH3 loss after soil pH returns to the pre-treatment level. Acid-modified biochar ( B 20-AM ) mitigates initial increase in NH3 loss and reduces reactive gaseous N losses. Both B 20 and B 20-AM play a significant role in mitigating N2 O emissions. B 20-AM coupled with AWD produces higher yield with lower reactive gas N losses and GWPN .